ao.c

   1 /* MMQ_AO_IMPL should be defined by the Makefile */
   2 #ifndef MMQ_AO_IMPL
   3 #  error MMQ_AO_IMPL not defined
   4 #endif
   5 #include "mmq.h"
   6
   7 struct afmt g_next_afmt;
   8 static struct afmt current;
   9 unsigned long g_sample_size;
  10
  11 static int matches_current(void)
  12 {
  13         /* no using memcmp because of potential padding */
  14         return ((g_next_afmt.rate == current.rate) &&
  15                 (g_next_afmt.bits == current.bits) &&
  16                 (g_next_afmt.channels == current.channels));
  17 }
  18
  19 /* this should statically define _my_open, _my_close */
  20 #include MMQ_AO_IMPL
  21
  22 int audio_open(void)
  23 {
  24         int rv;
  25
  26         if (matches_current())
  27                 return 0;
  28         if (g_next_afmt.channels != 2) {
  29                 warn("only 2 channel output is supported for now\n");
  30                 g_state = STATE_NEXT;
  31                 return -1;
  32         }
  33         audio_close(1);
  34
  35         rv = _my_open(&g_next_afmt);
  36         if (rv < 0) {
  37                 warn("ao_open failed\n");
  38                 g_state = STATE_NEXT;
  39         } else {
  40                 memcpy(&current, &g_next_afmt, sizeof(struct afmt));
  41                 emit("a%u:%u:%u\n",
  42                      current.rate, current.bits, current.channels);
  43         }
  44
  45         return rv;
  46 }
  47
  48 void audio_close(int graceful)
  49 {
  50         _my_close(graceful);
  51         memset(&current, 0, sizeof(struct afmt));
  52 }
  53
  54 int audio_inject(void *buf, long samples, conv_fn conv_i)
  55 {
  56         if (likely(g_state == STATE_PLAY))
  57                 return _my_inject(buf, samples, conv_i);
  58
  59         return -1;
  60 }
  61
  62 long audio_copy(void *dst, void *src, long samples, long offset)
  63 {
  64         src = (char *)src + (offset * g_sample_size);
  65         memcpy(dst, src, samples * g_sample_size);
  66
  67         return samples;
  68 }